I have shared a dashboard to one of my friend account (the dashboard created from an excel data stored in my google drive).Then it shows up on my friend ipad in "share with me" section. Once he clicked on the dashboard, they asks to enter my google drive account to import the data. This is not good because he can access my google drive account and see what i keep inside. What should I do if I want to share it without telling him my cloud account ( think of my friend can do "view only" and the dashboard keep updating if I update the raw data)

As William Said in this other post, you can share the files n Google Drive with the accounts that you want to have access to the data. Then, after the dashboard is shared within ReportPlus, the other user has to use that very Google Account when the import dialog is prompted.